
This arrangement allows the use of 2 Astron SS-30M power supplies to be used
to supply both 14v and 28v. Power supply #2 was modified so that it's negative
lead is no longer connected to its chassis, and therefore "floats". This is
accomplished by isolating the chassis from the black output connector. A small
wire from this connector is normally fastened to the chassis via a screw located
on the edge of the main PC board. Once released, shrink tubing is placed over
the open end of this wire.
Safety components: The 15v zener and 12v relay disconnect the 28v output unless
both power supplies are on. D1 and D2 prevent any reverse voltage from appearing
across either power supply.

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